The present invention relates to superconducting techniques, and more specifically, to an architecture for a superconducting cavity that forms an array of resonators.
Quantum computing employs resonant structures called qubits to store information, and resonators (e.g., as a two-dimensional (2D) planar waveguide or as a three-dimensional (3D) microwave cavity) to read out and manipulate the qubits. To date, a major focus has been on improving lifetimes of the qubits in order to allow calculations (i.e., manipulation and readout) to take place before the information is lost to decoherence of the qubits. Currently, qubit coherence times can be as high as 100 microseconds and efforts are being made to increase the coherence times. A superconducting 3D cavity can be made by mating two metal pieces with pockets that line up and constitute the walls of the cavity. The cavity may be made out of copper, which limits the quality factor of all resonant modes to approximately 10,000 since copper remains a normal metal even at dilution refrigerator temperatures. Aluminum cavities of the same variety produce quality factors ranging from 1 to 50 million depending on various cleaning, machining, and material properties.